Unit 2 Chapter 2 Psych Vocab

Biological Psychology

the scientific study of the links between biological (genetics, neural, hormonal) and psychological processes

Neuroplasticity

the brain’s ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience

Neuron

a nerve cell; the basic building block of the nervous system

Cell Body

the part of a neuron that contains the nucleus; the cell’s life support center

Dendrites

a neuron’s often bushy, branching extension that receive and integrate messages, conducting impulses toward the cell body

Axon

the segmented neuron extension that passes messages through its branches to other neurons or to muscles or glands

Myelin Sheath

a fatty tissue layer segmentally encasing the axons of some neurons; enables vastly greater transmission speed as neural impulses hop from one node to the next

Glial Cells

cells in the nervous system that support, nourish, and protect neurons; they also play a role in learning, thinking, and memory

Action Potential

a neural impulse; a brief electrical charge that travels down an axon

Threshold

the level of stimulation required to trigger a neural impulse

Refractory Period

a brief resting pause that occurs after a neuron has fired; subsequent action potentials cannot occur until the axon returns to its resting state

All-Or-None Response

a neuron’s reaction of either firing (with a full-strength response) or not firing

Synapse

the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron; the tiny gap at this junction is called the synaptic gap

Neurotransmitters

chemical messengers that cross the synaptic gap between neurons; when released by the sending neuron, they travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse

Reuptake

a neurotransmitter’s reabsorption by the sending neuron

Endorphins

“morphine within” --natural, opiate-like neurotransmitters linked to pain control and to pleasure

Agonist

a molecule that increases a neurotransmitter’s action

Antagonist

a molecule that inhibits or blocks a neurotransmitter’s action

Nervous System

the body’s speedy, electro-chemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems

Central Nervous System (CNS)

the brain and spinal cord

Peripheral Nervous System (PNS)

the sensory and motor neurons that connect the central nervous system to the rest of the body

Nerves

bundled axons that form neural cables connecting the central nervous system with muscles, glands, and sensory organs

Sensory (Afferent) Neurons

neurons that carry incoming information from the body’s tissues and sensory receptors to the brain and the spinal cord

Motor (Efferent) Neurons

neurons that carry outgoing information from the brain and spinal cord to the muscles and glands

Interneurons

neurons within the brain and spinal cord; they communicate internally and process information between the sensory inputs and motor outputs

Somatic Nervous System

the division of the peripheral nervous system that controls the body’s skeletal muscles; also called the skeletal nervous system

Autonomic Nervous System (ANS)

the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart)

Sympathetic Nervous System

the division of the autonomic nervous system that arouses the body, mobilizing its energy

Parasympathetic Nervous System

the division of the autonomic nervous system that calms the body, conserving its energy

Reflex

a simple, automatic response to a sensory stimulus

Endocrine System

the body’s “slow” chemical communication system; glands and fat tissue that secrete hormones into the bloodstream

Hormones

chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues

Adrenal Glands

a pair of endocrine glands that sits just above the kidneys and secretes hormones that help arouse the body in times of stress

Pituitary Gland

the endocrine system’s most influential gland; under the influence of the hypothalamus, it regulates growth and controls other endocrine glands

Lesion

tissue destruction

EEG (Electroencephalogram)

an amplified recording of the waves of electrical activity sweeping across the brain’s surface; these waves are measured by electrodes placed on the scalp

MEG (Magnetoencephalography)

a brain-imaging technique that measures magnetic fields from the brain’s natural electrical activity

PET (Positron Emission Tomography)

a technique for detecting brain activity that displays where a radioactive form of glucose goes while the brain performs a task

MRI (Magnetic Resonance Imaging)

a technique that uses magnetic fields and radio waves to produce computer-generated images of soft tissue; shows brain anatomy

fMRI (Functional MRI)

a technique for revealing blood flow and, therefore, brain activity by comparing successive MRI scans; show brain function as well as structure

Brainstem

the oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull; it is responsible for automatic survival functions

Medulla

the base of the brainstem; controls heartbeat and breathing

Thalamus

the brain’s sensory control center, located on top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla

Reticular Formation

a nerve network that travels through the brainstem into the thalamus; filters information and plays an important role in controlling arousal

Cerebellum

the “little brain” at the rear of the brainstem; functions include processing sensory input, coordinating movement output and balance, and enabling nonverbal learning and memory

Limbic System

neural system located below the cerebral hemispheres; associated with emotions and drives

Amygdala

two lima-bean-sized neural clusters in the limbic system; linked to emotion

Hypothalamus

a neural structure in the limbic system lying below the thalamus; it directs several maintenance activities, helps govern the endocrine system via the pituitary gland, and is linked to emotion and reward

Hippocampus

a neural center located in the limbic system; helps process explicit (conscious) memories–of facts and events–for storage

Cerebral Cortex

the intricate fabric of interconnected neural cells covering the cerebral hemispheres; the body’s ultimate control and information-processing center

Frontal Lobes

the portion of the cerebral cortex lying just behind the forehead; involved in speaking and muscle movements and in making plans and judgements

Parietal Lobes

the portion of the cerebral cortex lying at the top of the head and toward the rear; receives sensory input for touch and body position

Occipital Lobes

the portion of the cerebral cortex lying at the back of the head; includes areas that receive information from the visual fields

Temporal Lobes

the portion of the cerebral cortex lying roughly above the ears; includes the auditory areas, each receiving information primarily from the opposite ear

Motor Cortex

a cerebral cortex area at the rear of the frontal lobes that controls voluntary movements

Somatosensory Cortex

a cerebral cortex area at the front of the parietal lobes that registers and processes body touch and movement sensations

Association Areas

areas of the cerebral cortex that are not involved in primary motor or sensory functions; rather, they are involved in higher mental functions such as learning, remembering, thinking, and speaking

Neurogenesis

the formation of new neurons

Corpus Callosum

the large band of neural fibers connecting the two brain hemispheres and carrying messages between them

Split Brain

a condition resulting from surgery that separates the brain’s two hemispheres by cutting the fibers connecting them